Mathod of preparing materials for purifying illuminating-gas.



UNITED STATES PATENT OFFICE.

JOHN P. IHART, OF NEV YORK, N. Y.

METHOD OF PREPARING MATERIALS FOR PUlllFYlNG lLLUMlNATlNG-GAS.

SPECIFICATION forming part of Letters Patent No. 670,451, dated March26, 1901. Application liled November 21, 1900; Serial No. 87,233.ipeoimfi co unty, and State of New York, have invented ajnew and usefulMethod of Preparing Materials for Purifying Illuminating-Gas, of whichthe following is 'a specification.

My invention relates to the art of making materials suitable forremoving sulfdret'edhydrogen from illuminating or fuel gas; and theobject of my'invention is to prepare a material whichis as efficient asthat now=oommonly used, can be made active'in a much ofa'ir and water;but oxidation by this means requires a considerable length of time. Ihave discovered that'spent pyrites (the waste from the manufacture of'sulfuric acid, commonly known as pyrites-cinders and also the ironores-such as the hematites, for instancecan be used as a purifyingmaterial when subjected to my process.

In practicing my invention I preferably divide the pyrites-cinders orironores into small particles by any suitable process and spread suchore or pyrites-cinders in heaps from, say, four to eight inches high. Ithen wet the material with a weak aqueous solution of an acid that formsa salt of iron that forms a hydrate with an alkali in the presonce of aniron oxid and then add such alkali and mix it with the wet ore orpyrites-chr-Wns; The mixture is then ready for-immediate use as anactive purifying agent, and itcan either be used alone or it may bemixed with sawdust or other similar suitable material to produceporosity and provide greater permeability for the gas in the well-knownmanner. Although a. single wetting of the ore or pyritesscinderswith'the acid solution will make the compound active to some extent, Ihave found that it is'better to use the solution several timessuccessively, allowinga short inter= valof time between each wetting.Suitable acids for this purpose are sulfuric and hydrochloric acids, andthe waste liquors from ironpickling works or from chlorin-stills I have50.

found to be cheap and effective. Limexis a cheap and effective alkali,and I recommend that a surplus quantity of alkali be used in.

order to neutralize any free acid that may be present in the mixture.

I cannot explain the chemical reactions that take'place, but supposethat the acidl with a,

As the pyrites-cinders and the iron ores,

including thehematitemare all of the ore nature and are substantialequivalents for each other in myprocess, I include them all under' thegeneral term iron ore in the appended'claims, although I prefer the useof pyrites-cinders Having th us described I claim is- I l. The processof'prepariug a material f0!- purif'ying gas which consists in mixing together an iron ore, a weak aqueous solution, of an acid that forms asalt of iron that forms. a hydrate with an alkali in the presence of aniron oxid, and described. 2. The process of preparing a material forpurifying gas which consists in mixing inlny invention, what gether aniron ore, a weak aqueous solution as described.

JOHN P. lHAB/l.

Witnesses:

HARRY V. FOUNTAIN, J. E. llmnos HYDE.

an alkali, substantially as

